Bull gear lock



Jan. 30, 1945. T.' A. P. T. KoHT BULL GEAR LQCK Filed Aug. 14, 1945 4 @.1 j 9 2H? 55/52 f Patented Jan. 30, 1945 BULL GEAR LOCK v'Thorvald A. P. ThronsenKoht, Chicago, Ill., as-f' signor to Logan Engineering Co., Chicago, Ill., a corporation of Illinois l Application August 14, 1943, Serial No. 498,708

claims. (01.192-39) The present invention relates to bull gear locks,

. and is particularly concerned with devices for locking or securing the driving pulley of a lathe to the bull gear which is carried "by the spindle of the lathe, in such manner that vthe spindle' can be driven directly from pulley to bull gear to spindle when desired, instead of being driven through the back gears of the lathe at the reduced speed provided by the back gears.

One. of the devices of the prior art over which'- the present invention is an improvement, permits the securement ofthe bull gear of the lathe to the pulley; but the prior art devices are cumberson in operation and slow to operate, involving the turning of the pulley by hand until the bull gear and pulley reach a certain position of registration of the securing device. The devices of the prior art required particular attention in their manipulation, and more time for manipula-7 tion, thereby taking time and attention of the operator which might better be devoted to other operations. y

One of the objects of the invention is the pro-` vision of an improved and more simple form of bull gear locking device, which vmay be manipulated by the lathe operator with greater ease and withoutthe necessity for the particular attention and waste of time involved in the operation of the devices of the prior art.

Another object of the invention is the' provision of a locking device for the pulley and the bull gear of a lathe, of the class described, whichis sturdy, capable of economical manufacture and sale, and adapted to perform its functions for a' A long period oftime Without necessity for repair or replacement. I

Another object of the invention is the provision of an improved bull gear lock of the class Idescribed, which is so arranged that it is-only necessary to actuate a single lever, after which the securement of the pulley and bull gear together takes place automatically by virtue of springvaction of the device.

Another -object ofthe invention is the pro. vision of a device of the class vdescribed which is so constructed that its operationis guarded against centrifugal force acting upon the parts of the device, and which is simpleto operate and to release.

Other objects and advantages of the invention will be apparent from the following description and the accompanying drawing, in which similar characters of reference indicate similar parts throughout the several views.

v pinion 22.

' Referring --to the single sheet of-drawings accompanying this specification, Y

Fig. 1 is a side elevational view in partial section of a fragment of a lathe at the spindle end, embodying the invention;

Fig. 2 is a fragmentary vertical sectional View, taken von the plane of the line l2 2 of Fig. 1, looking in the direction of the arrows; I

Fig. 3 is a view in perspective, partially broken away, of the bull gear and the actuating'mechanism for the invention; and n Y Fig. 4 is a View in perspective of the mecha'- nism of the device, showing the spring and plunger in the course of ztheir being assembled.A as further described herein. y

Referring to the drawing, Fig. 1,A I 0 indicates in its entirety a lathe lequipped with a device embodying the invention. VThe lathey I0 is provided with the usual ,supporting framefmemberI I `:for

'f 20 the spindle end of the lathe I0, v`andwith'the bearings I2, I3, carried byfther housing I4,` for the spindle I5.

The lathe spindlel5 carries-*the bull gearlli,v

which is secured on the spindle I5 to rotate the spindle I5 by means of a key andkey'way- I'I.

A pulley I8, preferably of the ytype having a plurality of pulley portions vI9, 2f), 2|, of different diameters, is rotatably mounted upon4 the spindle I5 for free rotation with` respect tothe spindle, but is securedto the pinion y22- .to` rotate Pinion 22 is adaptedtovrnesh with and `drive the spur gear 23, carried by the tubular shaft 24, which also carries the pinion 25 adapted'to mesh with and drive the'bull gearI I6. The `tubular shaft 24 is movable by means of the eccentric portion 26 of la shaft 2'Imounted in bearings 28. By means of a rack (not shown) operating on the gear 29, the eccentric shaft 2I may be turned and the eccentric portionA 26 Will'bring the gears 22, 23, and I6, 25, into mesh with eachother, respectively, or it will move: these'gears outof mesh with each other; and the gear train 22, 23, 25 is usually referred to as the back gears of the lathe.

The-back gears driveithe spindle at a'reducd y rate of speed as compared with the'drive pulley speed (I8), and it is desirable toprovide the lathe with meansfor driving the vbull gear and spindle directly with the pulley I8 and at' the sames'peed,

as the pulley I8;`

For this purpose the bull vgear' I6 is preferably.'

body having a radially extending bore 34. 'Ihe .y bore 34 slidably supports a plunger 35, com- 39 of reduced cylindrical shape and the headfAll, which is elongated and provided with the plane side surfaces parallel to eachother. 'Ihe'head 40 is adapted to be received in the complementary, aperture 42, in the springl 43; and when v.the

plunger is .turned to a position at right angles to that of Fig. 4, with respect to the aperture 42,

the plunger Will be connected ito'the'vspring so that it will movewith the spring. f

The hub 30 is also provided with a projection 44 Ashaving*arbore fforreceiving the pin 2,46 and'y indicated by the numeral H5. The1pin`46 passes f ferably ibent lat 1491to 'extend transversely to ithe plunger 35,1and thealspring hasan=-actuating-por ftion 150 4extending beyond the .plunger 435 below I athenam52. V`'.I'hesspringfll's isroffse't fai-,15 ttobring its actuating portionrlliinto 'the proper :plane *.u'rges :the plunger upwardrinlFig. 2 .andfpresses uagainstrthefcam, which isadapted to Withdraw the plunger 35 by actingon` the spring-43.

l .nrorder to l-imitthemotionof the plunger 35, ritliefguide :body-"33 iis sprovided with v.a :transverse -borefii 'intersectingf the bore 534,whichfcontains the -plunger35at suchfpointathatapin 54 inxbore `:'53 Iengagesfthe flat .'side y.offplunger '35 and V:serves toipreventthe rotation of theplunger 3.5.

This pin 54 hasl a tight frictional tinits :bore53, rami-it also servesito-stop the sliding-:motion of` :the-plunger Y35 When-'thershoulders 31, 38 l'enga-ge fthe# pin 15'4.

Thezpini5'4 :thus serves *to ilimit the sliding `movement :of the 'plunger 35 .and :to .prevent its disengagement from fthe spring 43.

The'wheelv flange 31: ofA theifbull gear lfis preflenablypreviden:witha through bore 55=for vreceiving the hub portion 56 of the cam 52 Whichis'held said:.borefby aatransverseipin-TSI carriedlby-hub' y.portion :5B and i engaging rthe r :Wheel flange 32|.

"'Thefcanrmemberi 521 hasa-thrust flange 58 and an '.integraliballeshaped: shaft extension 59 u provided fwvithvavradial actuating' Varm'lll. 'The .parts '59 fandlzare smoothlyfnished andfrounded so 'that ftheymay be graspedbyfthe ngers ofy the-operator 1withoutzlocking. and4 without injury tothe ngers.

' SAtcits opposite end thecam lmember-52 is'profvided with as'lot-zllnrof sucientwidthto receive :thefactuatingzpoiztion oitheespring 43,;and the sslothasgaepth which :corresponds substantially l'atritheginoitement desired zfor.:.the :plunger `35.

When the spring 43 is in the slot 6|, the'springfllav mermitted v`to .fmnverupward ina-Figjz .tonsu'ch a ;point that therplunger 315protrudesf from its guide Lbore .34 v.andfextends.into engagement ywith .the inside ofthe wheellilange ll-.tor projectsintofone .ofseuer-al bores-.62.in thevwheeli'lange t5. When the handle 60 is rotated through anarc .of 180 r.deg1:ees,.the cylindrical .portionfil of: cammember '52s engages .spring 43 and fforces thespring .downaward .in Fig. 2, tov Withdraw .the plunger 35 "from .borefznthe pulleyiportion lf9zof pulley i8.

Then the bull gear is disconnected yfrom the pulley I8, but Whenthe cam member is in the position of Fig. 2, the bull gear and pulley I8 areI connected to rotate together. Whenever it is 5 desired to connect the bull gear to the pulley, it is not necessary to turn either of these parts until the'position of registration of the plunger and a .borelZfis found; it isefonlynecessary to turn the cam member 52 by means of handle 160. Then 10 the spring'pressurewill be placed on the plunger -35, and it will ride onfthe inside of the wheel or pulley flange I9 until vit automatically snaps into a .bore 62 and connects the bull gear and pulley.

The .operation Vofmy invention will be apparent 'ljjfro'm thefforegoing description. The assembly .o'f.the..partswill` also be apparent, except that it should be noted that the plunger has its head 4| first insertedifintofthe slot 42, and then turned .ninety degrees. Then the plunger may be inserted in the bore 34, and when the pin 54 is 'zdriven :into place, 1'. its :engagement with the at fside'BB-xo'f the' plunger preventsithexplunger from rotating, andkeepsfthe head-4l extending-translverselyv to the felongated ,aperture .42 so 'that th f :head .cannot-getroutnf .the aperture.

The :back gears .should, of fcourse, -falways :be withdrawnb'efore connecting the. bull gear `and theipulley f 1- ,i

It will thus Abe observed that I have invented van igvrimproved device .forlocking the bullgear hand ...pulley together, Which-is simple, and which is .adapted .to-,placer spring pressure on the plunger .sothatthe plunger..autonriatically snapsinto.-` lock- .ing position. Thepresent lockingdevice .can be 535. .operatedin a fraction of the time required yfortlie .devices .of .the prior art. The .bullgearmay be counterlo'alanced at .64 tocornpensate for -the-.ad-

ditional Weight `of .the .locking device, .whichis .located diametrically .oppositeto the counterbali140 ance.l

. While kl'fhave .illustrated yand described a preferred embodiment of my invention, manymodications may .be .made .Without-,departing .from the spirit off the invention, andl do not Wish tobe IAti limited tothe pre'cisefdetails of oonstructions'et -forth, butedesire to avail myself of .al1 lchanges within the scopegoff the appended claims.

Having thusdescrib'ed vmy invention, what I 'l claim as new and desire Ato secure by Letters .Patentof the United states, is:A l

1. In a'device "for 'flocking the bull 4gear lof a lathe tothe .drivingpulley, the combination of a y Ibull gear lcarriedlby'the spindle of a-lathe, with "adrivingpulley mounted onsaid spindleforfree '.55rotation, said pulley 'having a radially extend- 'ing aperturednits pulley flange, guide means carried by said bull gear, for slidablysupporting a-'lockingplungen agplunger in said guide means, vand "manually vcontrollable spring-means for lurging /sai'd plunger in a` direction to `engagein said aperture', whereby theplunger mayride on 'the inside of the pulleyy until plunger and aperture are vin Aregistry :and :then r4thefplunger' is snapped into the aperture to lock theA bu`l1= gear vfand-pulley L `'together for simultaneous rotation, 7said vplunger "havingfa substantially Tshapedfhead, said spring .means being provided with .a;comp1ementary laaperture for :receiving/said head, :said `plunger ,':bein-g'rotated infsaid, aperture torcausefthefspring v means to become attached to said plunger.`

i2. .1n :a .device zfor. locking the bull :gear-'fof a 'lathe ato the .driving pulley, the combination :.o'fza hull gear.A carried byythe V'spindlefof -a lathe, vwith, 1a..:drivingtpulley..mountedzonesaid spindle .sfor rfree 15 rotation, said pulley :'havingz a' radiallyextendinfg aperture in its pulley flange, guide means carried by said -bull gear, for slidably supporting a locking plunger, a plunger in said guide means, and manually controllable spring means for urging said plunger in a direction to engage in said aperture, whereby the plunger may ride on the inside of the pulley until plunger and aperture are in registry and then the plunger is snapped into the aperture to lock the bull gear and pulley together for simultaneous rotation, said manual means comprising a rotatable cam for engaging said spring and for retracting said spring and p1ungersaid plunger being of substantially cylindrical shape and provided with a ilat side portion, said bull gear being provided with'a pin extending transversely to said plunger and engaging the fiat side of said plunger to prevent rotation of said plunger.

3. In a device for locking the bull gear of a lathe to the driving pulleythe combination of a bull gear carried by the spindle of a lathe, with a driving pulley mounted on said spindle for free rotation, said pulley having a radially extending aperture in its pulley ange, guide means carriedv by said bull gear, for slidably supporting a locking plunger, a plunger in said guide means, and manually controllable spring means for urging said plunger in a direction to engage in said aperture, whereby the plunger may ride on the inside of the pulley until plunger and aperture are in registry and then the plunger is snapped ,into the aperture to lock the bull gear and pulley together for simultaneous rotation, said manual means comprising a rotatable cam for engaging said spring and for retracting said spring and plunger, said plunger being of substantially cylindrical shape and provided with a ilat side portion, said bull gear being providedwith a pin extending transversely to said plunger and engaging the at side of said plunger to prevent rotation of said plunger, said plunger also having shoulders at each end of said flat side portion and said pin engaging said latter shoulders to linut the sliding movement of said plunger.

4. `In a lathe drive, the combination of a supporting frame with a lathe spindle having a bull gear mounted on said spindle for rotation with said spindle, a pulley mounted on said spindle for free rotation with respect to said spindle, said 1 plunger to lock said bull gear to said pulley for rotation with said pulley or to release said bull gear from said pulley, said plunger having a flat side portion and stop shoulders at the ends of said flat portion, and a pin extending transversely to said plunger, said pin preventing rotation of said plunger and limiting the sliding movement of said plunger.

5. In a device for locking the bull gear of a lathev to the driving pulley, the combination of a shaft provided with a bull gear keyed to said shaft, a multiple pulley member rotatably mounted on said shaft and having an open end at its largest pulley adjacent saidfbull gear, said -bull gear having a laterally projecting lug extending inside the open end of said multiple pulley member, a plunger slidably mounted in a radially extending bore in said lug, said plunger being adapted to register with an aperture in the periphery of the largest pulley of said multiple pulley member, spring means for urging said plunger into said latter aperture, stopmeans for limiting the movement of said plunger, and manual means for blocking the action of said spring means and maintaining said plunger out of engagement with said pulley member at will.

THORVALD A. P. THRON SEN KOHT. 

